【作者】 蒋玲；

【导师】 卢健；

【作者基本信息】 武汉大学 ， 摄影测量与遥感， 2004， 硕士

【摘要】 随着计算机技术、网络通讯技术、地球空间技术的发展，万维网地理信息系统正成为大众化的信息工具，越来越多的Web站点提供空间数据服务。但是由于行业政策和数据安全等客观的原因，这些空间资源大多是存在于特定的GIS系统和桌面应用中，各自为政，相对封闭，从而形成空间信息孤岛，难以满足Internet上空间信息决策所需要的共享的要求。传统的三层WebGIS构造模型，以及后继发展的基于中间件的分布式WebGIS构造模型，无论它们是采用RMI、DCOM还是采用CORBA等分布式对象技术，虽然在实现网络负载平衡、分布式计算等方面有了较好进展，但对解决开放式地理信息服务平台中的异构系统间的互操作及跨平台的数据集成与共享等核心问题上仍然无能为力。 XML在复杂数据编码和信息交换中有着明显的优势，是解决当今WebGIS所面临主要问题的有效途径。Web Service是一种解决在异构网络环境下建立分布式系统的又一全新的网络构架技术。基于XML Web Service的WebGIS具有分布式、可互操作、方便集成、扩展性良好的特点，是WebGIS的发展趋势。本文着重于探索新的网络技术XML技术和WebService技术，及其在地理信息领域的应用，提出以XML Web Service体系构造WebGIS平台。本文的研究主要完成以下工作： 1．本文首先介绍了国内外WebGIS发展现状，WebGIS的概念与特点，开放性地理信息互操作平台(OGC)，然后比较分析了当前WebGIS主要的开发技术和实现策略及其利弊，指出了当今WebGIS存在的主要问题是：使用不同产品开发的系统之间地理数据不能充分共享，相似的功能不能互操作。 2．本文分析了目前XML在WebGIS中的应用状况，研究了OGC发布的简单要素模型和地理数据编码标准GML，详细论述了基于GML的地理编码的特点和相关技术。最后得出采用XML／GML作为地理数据存储和传输的载体可以方便地实现多源异构地理数据的集成和共享的论证。 3．本文对Web Service的核心技术：简单对象访问协议SOAP(Simple Object AccessProtocol)、网络服务描述语言WSDL(Web Service Description Language)、统一描述，发现和集成UDDI(Universal Description，Discovery and Integration)进行了较深入地探讨。利用Web Service可以搭建一个松散耦合的WebGIS环境，给GIS的Web应用带来了全新的设计理念。 4.在参考OGC的开放式地理网络服务模型基础上，本文提出了一个基于XML Web Service体系的开放式WebGIS设计方案，并给出各项主要服务的接口设计。最后 根据上述方案设计开发了一套简单的原型系统，验证了该设计方案的正确性和可行 性。 基于XML Web service的webGIS是一个崭新的研究领域。基于GML的空间数据建模技术和数据转换技术以及基于Web Service的系统构架技术的研究与发展都会给传统的WebGIS技术带来极大的冲击，对传统Web(且S的方方面面的应用都将产生深远的影响。目前，国内外对这方面的研究理论上己基本成熟，但实践上由于行业标准束缚、网络固有的问题限制以及原有WebGIS系统的拘囿等多方面的原因，许多工作还处在试验阶段，基于该技术的成熟的WebGIS网站在国内外还不多见。 本文对基于XML/GML、Web Service技术的WebGIS理论进行了的初步的探讨与研究，利用Xws(XML web service)体系构建的一个网络地图服务原型系统与实际的webGls应用系统也存在很大的差距，难免有疏漏和不足之处，敬请不吝指正。更多还原

【Abstract】 With the development of the computer technology, network communication technology and the earth space technology, WebGIS is becoming a popular information tool, more and more Web websites offer space data services. But we have to face such a reality: It is unable to well communicate and cooperate between tens thousands of Web websites, and it is very difficult to visit, deal with distribute magnanimity space datum in Web through browser. Because the reasons of enterprise policy and data safety, the space resource mostly exist in specific GIS systems or tabletop applications, doing things in their own way and close relatively, thus the detached space information islands are formed. It is difficult to meet the need of the sharing of space information on Internet. Traditional three-ply WebGIS model and subsequent distributed WebGIS model based on the middle part, No matter they adapt RMI, DCOM or adapt distributed object technology, such as CORBA etc, though there is better progress in realize the balance of the network load, distributed calculation, etc, but it is still powerless to solve the operation each other and data integration etc between isomerous systems on the platform of open geographical information service.XML (extensible Markup Language) has obvious advantage in complicated digital coding and exchanging with information; it is an effective way to solve the subject matter that WebGIS faces. Web Service is another brand-new technology to set up distributed systems in the internet environment. WebGIS based on XML Web Service has characteristics of distributed, capable of operation each other, being convenient to integrate. It is a trend of WebGIS.The thesis focuses on exploring the new network technology of XML and Web Service, and studying the application in the field of GIS based on the both, then proposes constructing a WebGIS platform with XML Web Service system. The research of this thesis finishes the main work as follow:I. The thesis has introduced the current development situation of WebGIS , the concept and characteristic of WebGIS and Open GIS Consortium (OGC) firstly. Then it analyzes comparatively the main development technology, tactics of realizing and their advantages and disadvantages in nowadays WebGIS. Have pointed out that nowadaysthe subject matter that WebGIS exists is: the systems developed by different G1S software products can not fully share in geographical data, and the similar functions can’t operate each other.II. The thesis has analyzed XML application situation in the field of WebGIS at present, has studied "Simple Feature Model" and GML that OGC issues, and has described the characteristic and relevant technology of GML in detail. Then it is concluded that adopting XML and GML as the carrier of geographical data storage and transfers can be convenient to realize the integration and share of many isomerous geography datum.III. The thesis has relative deeply discussed the three key technologies of Web Service: these are SOAP (Simple Object Access Protocol), WSDL (Web Service Description Language) and UDDI (Universal Description, Discovery and Integration). Using Web Service to set up a WebGIS environment of loose coupling can bring a brand-new design idea for the GIS application.IV. On the basis of consulting the open geographical network service models of OGC, the thesis has put forward an design of open WebGIS scheme of based on XML Web Service system, and provided design of every main service interface. Finally, the author developed a set of simple prototype systems according to the scheme; then it has verified the exactness and feasibility of the scheme.The study of WebGIS based on XML Web Service is a brand-new research field. The space data modeling technology and data transform technology based on GML, and the system framework technology based on Web Service bring a great impact on traditional WebGIS.At present, the domestic and international study on this respect has been already rip basically in theory. Whereas in practice, because of t更多还原